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  <meta charset="UTF-8">
  <meta name="Generator" content="EditPlus®">
  <meta name="Author" content="">
  <meta name="Keywords" content="">
  <meta name="Description" content="">
  <title>Document</title>
 </head>
 <body>
	<input type="text" id="num">
	<input type="button" onclick="bian()" value="判断">
 </body>
	 <script>
	
	function bian(){
	var x = num.value;
	if (x%400==0 || (x%4==0 && !(x%100==0)))
	{
		document.write("闰年");
	}else{
		document.write("不是闰年");
	}
	}
  </script>
</html>
